The invention furthermore relates to a cellular system which has a land mobile network with a plurality of cells in which cell terminals can check-in for use of the services of the cellular system, each cell being identifiable by an emitted cell identifier, use being limited/limitable to closed subscriber groups by the cell having a corresponding identifier and the cell terminals being checked into the respective cell for use of the land mobile network services only after a positive matching with a positive list of authorized cell identifiers stored in the cell terminal.
These cells for so-called closed subscriber groups (CSG) are consequently known. These CSG cells are identified by a cell identifier emitted from the CSG cell or cell identity (CSG-ID) which is emitted by the CSG cell. A cell terminal, also called user equipment (UE), then tries to check into such a CSG cell only when the cell identity CSG-ID received by the cell terminal (UE) and emitted by the cell is contained on the positive list (white list) which supports the cell terminal UE and the cell terminal is thus identified as belonging to the closed subscriber group (CSG).
Cell terminals which do not belong to the closed subscriber group (CSG) cannot check into this cell so that in this way use of the services of the land mobile network is not possible for these cell terminals. Only an emergency call can be transmitted. General use of the network services is however not possible.
The disadvantage is that it is not possible for the operator of such a cell for closed subscriber groups to enable the cell for checking-in and using the land mobile network services for other cell terminals, even if this is desirable since the operator of such a cell does not have access to the positive lists (white list) of authorized cell identifiers stored in the different cell terminals.